This topic explains how to use the Exchange Management Shell to configure your Microsoft Exchange deployment to handle mailboxes that are moved from one forest to another for the Autodiscover service.

For a cross-forest mailbox move, the two forests must be trusted. For the Autodiscover service to handle this move, you must configure a mail contact in the original forest where the user's mailbox resided.

When you configure a mail contact, the user will authenticate to the original forest where the mailbox resided, and the user will receive a redirect that uses the new e-mail address. The client will then try to contact the Autodiscover service by using the new e-mail address against the new forest.

For example, mail1.contoso.com and mail2.contoso.com are separate, trusted forests and the mailbox for a user is kwekua@mail1.contoso.com. This user originally resided in the forest named mail1.contoso.com and was moved to the forest named mail2.contoso.com.

For this example, you have to set a contact in mail1.contoso.com by using the following command in the Exchange Management Shell: